diff --git a/requirements/requirements-optionals.txt b/requirements/requirements-optionals.txt
index 87ae27199..54c080491 100644
--- a/requirements/requirements-optionals.txt
+++ b/requirements/requirements-optionals.txt
@@ -2,4 +2,4 @@
 markdown==2.6.4
 django-guardian==1.4.3
 django-filter==0.13.0
-coreapi==1.21.0
+coreapi==1.21.1
diff --git a/rest_framework/routers.py b/rest_framework/routers.py
index 0dfb2bb48..789f0217f 100644
--- a/rest_framework/routers.py
+++ b/rest_framework/routers.py
@@ -30,7 +30,6 @@ from rest_framework.reverse import reverse
 from rest_framework.settings import api_settings
 from rest_framework.urlpatterns import format_suffix_patterns
 
-
 Route = namedtuple('Route', ['url', 'mapping', 'name', 'initkwargs'])
 DynamicDetailRoute = namedtuple('DynamicDetailRoute', ['url', 'name', 'initkwargs'])
 DynamicListRoute = namedtuple('DynamicListRoute', ['url', 'name', 'initkwargs'])